What is dioptric correction?
Many people who wear glasses don t like wearing them when they look through the viewfinder. The glass bumps up against the eyecup, so you can t get your eyes close to the viewfinder. This makes it hard to see the entire image, particularly with EOS cameras which are notorious for not having the greatest viewfinders in this regard. But obviously if your eyes require corrective lenses then you won t be able to look through the viewfinder if you take your glasses off. At least not if you couldn t adjust the focus of the viewfinder itself. This is what dioptric correction does – it lets you adjust the viewfinder so that spectacles-wearing photographers can see through it sans glasses. Cameras with built-in dioptric correction have tiny dials or sliders located next to the viewfinder. Moving these controls adjust the viewfinder focus point. Note that you aren t out of luck if your camera lacks such correction facilities and you want it. Canon sell small add-on lenses which clip directly ont
